This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The fibrous collagens are the fundamental constituents of the Extracellular Matrix (ECM) of animals, forming the structural basis of all known mammalian connective tissue: bones, skin, cornea, teeth, tendons, ligature, blood and lymphatic vessels and all organ systems including the heart and lungs. Yet, despite the fundamental biological importance of collagen, the general-knowledge understanding of collagen is limited to its triple-helical 'secondary'structure or of the heavy metal stained electron microscopy images of whole fibrils A significant aspect of collagen structure from a cellular and biomedical point of view, however, is at the intermediate sub-fibrillar level, where many important biological processes occur in growth, development and disease. These include but are not limited to: fibrillogenesis, tissue remolding during normal growth and development and following exercise, and in forming the scaffolding upon which organ systems, bones, cartilage, etc., i.e. the animal body, are built upon. Clearly, obtaining an unambiguous and contextualized visualization of collagen molecules (within connective tissue) would be of significant value to the scientific community. Therefore, the aims of this proposal are to: 1) To structurally characterize the fibrillar collagens types II and I by fiber crystallography. 2) To structurally characterize the molecular organization of extracellular matrix molecules commonly found complexed with the collagens via fiber crystallography and bioinformatics / computational methods.3) To develop fiber crystallography and Micro X-ray Diffraction ([unreadable]XD) techniques that enhances the chance of successful completion of aims 1 and 2.